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Viagra - (Sildenafil)

Viagra (sildenafil) relaxes muscles and increases blood flow to particular areas of the body. Viagra is used to treat erectile dysfunction (impotence) in men.

What is Viagra?

Erectile dysfunction (sometimes called impotence) means that you cannot get or maintain a proper erection. There are several causes, the most common being due to a narrowing of the arteries that take blood to the penis.

Viagra works by preventing the action of a chemical in the body called phosphodiesterase type 5. This helps to relax (widen) blood vessels and improves the flow of blood. In erectile dysfunction, viagra improves the blood flow to the penis following sexual stimulation, and this helps to maintain an erection.

Viagra is available on prescription.

Do not take it if you do not have erectile dysfunction.

Before taking viagra

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking viagra it is important that your doctor or pharmacist knows:

If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines. It is important that your doctor knows if you are using a medicine prescribed for angina pain, or if you are using a 'nitrite' drug.

How to take viagra

Before you take viagra, read the manufacturer's printed information leaflet from inside your pack. The leaflet will give you more information about the tablets, and also a full list of the side-effects you may experience.

Take viagra exactly as your doctor has told you. You should take one tablet one hour before you plan to have sex. You can take the tablet before or after food but, if you have just eaten a large meal, it will take longer for it to work.

Do not take viagra more frequently than once a day.

What should I avoid while taking Viagra?

Avoid drinking alcohol, which can increase some of the side effects of Viagra. Avoid using other medicines to treat impotence, such as alprostadil or yohimbine without first talking to your doctor.

Viagra side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. During sexual activity, if you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw, stop and call your doctor right away. You could be having a serious side effect of Viagra.

Stop using Viagra and call your doctor at once if you have a serious side effect such as:

Please Note: We have made every effort to ensure that the content of this information sheet is correct at time of publish, but remember that information about drugs may change. This sheet does not list all the uses and side-effects associated with this drug. For full details please see the drug information leaflet which comes with your medicine. Your doctor will assess your medical circumstances and draw your attention to any information or side-effects which may be relevant in your particular case.